This Competitive Revision is in response to Notice Number NOT-OD-10-032 with Notice Title: NIH Announces the Availability of Recovery Act Funds for Competitive Revision Applications (R01, R03, R15, R21, R21/33 and R37) through the NIH Basic Behavioral and Social Science Opportunity Network (OppNet). The Revision specifically addresses the epigenetic/ genomic area under the topic of interactions between biology, behavior and social processes. The first year after childbirth is highly stressful for many mothers, but enhanced activity of the "bonding hormone" oxytocin (OT) may decrease blood pressure (BP), sympathetic nervous system (SNS) and hypothalamic-pituitary adrenal (HPA) activity and stress behavior, while increasing positive affect and activation of central reward pathways during mother-infant contact. For young parents with limited financial resources, part of the stress of adding a baby to the family is additional financial burden. This financial strain may have been increased during the current financial crisis by job loss or reduction of income to one or both parents. Supported by the parent R01 grant, we are examining OT responses of mothers who did vs. did not return to full-time work in the first 3 months after delivery, using plasma, saliva and urinary OT measures. Recently, in an unrelated series of studies, our research group has begun to examine novel genomic biomarkers. We now propose to revise this R01 grant by examining gene expression markers related to 3 systems: 1) oxytocinergic, 2) the HPA axis and 3) the SNS. We propose to compare these targeted gene expression markers in 60 mothers of infants grouped according to breast-feeding vs. bottle-feeding status, whether the mother experiences regular separation stress due to early return to work, and whether the family setting includes high vs. low financial stress. This research will be the first to examine OT gene expression on human leukocytes, and the first to examine the influence of life stress on OT, SNS and HPA gene expression markers together. PUBLIC HEALTH RELEVANCE: This Competitive Revision to R01 HL084222 is designed to expand the biobehavioral study of oxytocin's role in cardiovascular benefits for mothers of infants by incorporating novel leukocyte gene expression measures obtained before and after stress in 60 of these mothers. The Revision will examine genes linked to oxytocin activity, sympathetic nervous system activity and HPA axis activity, and it will also provide full-time employment to a black prospective medical student of Haitian descent as well as part-time support for other faculty and staff.